The present invention refers to a simplified rolling bearing unit of the type referred to as an insert bearing unit, incorporating an outer race ring having a spherically curved outer envelope surface and a circumferential groove provided in the inner envelope surface, and an inner race ring having an outer envelope surface with a circumferential groove and an inner envelope surface with a tapering saw-tooth profile extending in the axial direction of the inner race ring, a thin-walled sleeve, which is slotted by means of an axially extending slot and has a tapering saw-tooth profile on its outer envelope surface, cooperating with the saw-tooth profile in the inner envelope surface of the inner race ring for increasing and decreasing the grip of the thin-walled sleeve against a shaft, when the inner race ring and the thin-walled sleeve are displaced axially relative to each other, a flange member being connected to the exterior of the thin-walled sleeve and provided with a tightening member operable to cause the mutual displacement between sleeve and inner race ring, the grooves in the outer and inner race rings being positioned in such a manner relative to each other so as to form together a race track for a number of balls positioned between the grooves.
Such a bearing unit is for instance disclosed in EP 0 967 404 A2, where the flange is provided with a set screw inserted in a bore having its axis inclined towards the axis of the inner race ring and having a front end engaging one side face of the inner race ring.
PCT/SE2006/001454 refers to a two-row spherical roller bearing wherein the inclined set screw is arranged to act against a loose thrust flange positioned between the end of the set screw and the inner race ring of the bearing, said loose thrust flange having a sloping side face facing the set screw, with such an inclination that the free end of the set screw acts perpendicularly against the surface of the loose thrust flange.
In both these bearings the saw-tooth profiled inner envelope surface of the inner race ring has been subjected to machining incorporating a finalizing grinding operation. The resulting bearing units have proven themselves to be efficient and reliable, although the manufacturing costs are rather high.